AUSTRALIA'S wheat industry may be winning the battle against stripe rust.
After suffering from a wave of new pathogens attacking wheat varieties during the past few years, data from the National Variety Trials program indicates the tide is turning in the fight against the fungal disease.
The NVT program is a national system set up to independently test the performance of cereal, canola and pulse crop varieties at a number of trial sites across Australia.
Colin Wellings, of the University of Sydney's Cereal Rust Laboratory at Cobbitty, near Camden in NSW, said the data from the NVT program on stripe rust in wheat was promising, although some caution needed to be exercised over a new disease pathotype, which emerged late in the season.
"As we look at the advanced trials, we can see material in the near-to-release category looking good," Dr Wellings said.
"There is reason to believe, on that basis, that we can and are getting on top of stripe rust from a breeding point of view.
"There is reason to be optimistic."
Dr Wellings said it was a credit to plant breeders, who had made the breeding selections to develop resistant wheats.
"They have done a good job," he said.
"And they have been ably supported by the Australian Cereal Rust Control Program backed by the Grains Research and Development Corporation.
"That is an enormous cost benefit to grain growers."
Dr Wellings said a teleconference meeting this week would be held with state authorities to review the varietal responses to rust diseases.
The data would then be sent to plant breeders for comment for 10 days.
After that, the variety responses would be made available to growers to help them to select varieties for next season.
Dr Wellings said that, while progress in disease control had been made, there were "still some unknowns".
A new stripe-rust disease pathotype had emerged late in the season, which attacked the Yr27 resistance gene in some varieties.
He said the new potential threat had been named the Jackie Yr27 pathotype.
That was because it was derived from the Jackie disease agent which was dominant last year.
Varieties such as GBA combat, GBA ruby, merinda and mira relied on the Yr27 gene for resistance to stripe rust.
Dr Wellings said livingstone also carried the Yr27 gene but was expected to remain resistant to the Jackie Yr27 pathotype because it also carried the Yr17 resistance gene for protection.
While plant breeding provides the best long-term means of controlling the disease, wheat growers may still need to use fungicides and spraying of potential host plants over summer in their arsenal against stripe rust.
The GRDC said the use of fungicides at sowing time could protect triticale and early-sown wheat seedlings from stripe-rust attack and reduce disease build-up.
That could gain growers extra time to determine which type of rust strain was present and potentially eliminate some foliar fungicide applications.
